1. Field of the Invention
The invention relates generally to steering columns and more particularly to collapsible steering columns.
2. Related Art
Steering columns must remain functional while experiencing the forces generated in normal use, and preferably absorb the forces encountered in crash conditions to reduce injury to a driver. Typically, steering columns are designed to collapse in a telescopic manner during crash conditions so that the driver of a vehicle encounters a reduced impact force if the driver hits the steering wheel. Known designs of collapsible steering column assemblies have a steering shaft inside of a generally concentric cylindrical jacket, and in a crash condition, both the steering shaft and the jacket collapse in a telescopic fashion to lessen the impact to the drive. The jacket of the steering column commonly has a mounting bracket that is fastened to the vehicle so that during impact, the bracket can shear away from the vehicle and travel with the jacket while the jacket is collapsing. The jacket of the steering column and the mounting bracket are commonly formed as separate pieces and then fixed to one another by welding the two pieces together. The mounting bracket has inserts molded therein to allow the bracket to shear away from its mounted location. During collapse, the jacket and steering shaft are free to move in a generally unguided direction. The jacket, typically being metallic and having a mounting bracket welded thereto can be a relatively heavy and costly component. For this reason, it is desirable to reduce weight and cost in a steering column assembly, while maintaining the integrity and collapsing characteristics required in a steering column assembly.